No. 569] SHORTER ARTICLES AXD DISCUSSION 



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types, the apparent object brine to preserve the results of elimi- 

 nation, even though the theory had to be abandoned. Probably 

 it is only a question of time until the results of elimination will 

 be discarded, as well as the theory, and replaced by the actual, 

 historical types. 



A plan for determining the historical types of genera was 

 adopted in 11)07 in the American Code of Botanical Nomencla- 

 ture, and other applications of the method of types are being 

 rocognized by zoologists. Specialists in many groups are en- 

 gaged in the study of generic types, and the need of a special 

 terminology to facilitate work of this kind is becoming appar- 

 ent. Thus in Bulletin 83 of the U. S. National Museum, "Type 

 Species of the Genera of Ichneumon Flies," by Henry L. Vie- 

 reck, two new terms, "isogenotypic" and "monobasic," are em- 

 ployed in treating of the application of generic names to type 

 species. The paper is of interest, not only to students of this 

 group of insects, but also as an example of the tasks that con- 

 front all taxononiists who appreciate the need of basing their 

 work upon types. The distinctions to which the special terms 

 refer are undoubtedly useful, and the possibilities of express- 

 ing them in more convenient form are worthy of consideration. 



The word "isogenotypic," is used with reference to cases 

 where two or more generic names have been applied to the same 

 type species. 2 For this purpose a new term is not needed unless 

 zoologists are unwilling to borrow from botanical nomenclature 

 a more convenient method of treating the same class of cases. 

 The botanical code provides a classification of synonyms, and 

 applies the word "typonyin" to a name that has to be rejected 

 because an earlier valid name was proposed for the same type. 

 The formation and use of typonym are in accord with a familiar 

 analogy. As a preoccupied name becomes a homonym, it is easy 

 to remember that the use of a preoccupied type results in a 



